This invention relates to a method of presenting menu information, relating to the operation of an accessory unit which has no user interface, when the accessory unit is used with a base unit. The invention also relates to a base unit and an accessory unit suitable for such use. For example, the base unit may be a mobile phone.
Devices such as mobile phones have user interfaces, which allow their users to receive information relating to the status of the device. For example, the user interface may present such information in the form of a menu of available options, which allows the user to scroll through a list of headings, each of which may provide access to a list of sub-headings or available features, eventually selecting a desired feature. Such devices are commonly used with accessory devices which have no user interface.
There is therefore a need for a system which allows a user to select operating features of an accessory device, through a menu structure presented on a user interface of a base device.
Advantageously, the base device should be able to support a range of accessory devices, including accessory devices which have not been conceived of when the base device is designed.
WO98/00993 discloses a method and a device for handling user menu information in a mobile telephone. The mobile telephone stores at least one standard menu. When an accessory is connected to the mobile telephone, it can send a signal selecting a standard menu and including data for adaptation of the standard menu. For example, it may be preferable to include text which identifies the type of accessory in use.
In devices such as mobile telephones, it is a constant concern to minimise the size and weight of the device. This means that it is desirable to minimise the memory usage requirements of such devices. It is therefore desirable to avoid the need to store standard menu structures, as described above with reference to the prior art.
According to aspects of the invention, there are provided base devices, accessories, and methods of operation of accessories in combination with base devices. A base device is able to support an interface updating protocol. An accessory is able to operate the same protocol. When the accessory is connected to the base device, the base device interface can provide the user with an interface which allows him to control operating features of the accessory.
Preferably, the base device is a mobile phone. Preferably, the interface of the base device includes a display, which lists available operating features in a menu structure, and a user input means, for example in the form of a keyboard.
In preferred embodiments of the invention, all menus, relating to the accessory, are stored dynamically within the base device. Thus, there is no permanently available menu structure stored within the base device. Rather, when an accessory is first connected to a base device, a first menu is sent from the accessory to the base device. The menu is displayed for user selection. When the user has made a selection, a sub-menu may be sent from the accessory to the base device and displayed. When the user has made a selection from the sub-menu, a control signal is returned to the accessory, but information relating to the sub-menu may no longer be stored in the base device.
Advantageously, therefore, all subsequently developed accessories can be made compatible with existing base devices, by incorporation therein of suitable routines in the selected interface updating protocol.
Moreover, the use of dynamic storage of the menu items within the base device means that the requirement for usage of memory within the base device is greatly reduced.
Preferably, communications between the base device and the accessories take place using the well-known AT protocol. This has the advantage that, when the base device is a computing device, such as a hand-held computer, or PDA (personal digital assistant), which will need to be able to support this protocol for other reasons, there will be no additional requirement for protocol support.
Although the AT protocol is known for controlling modems when they are connected to computers, the preferred embodiments of this invention use the AT protocol for controlling accessories other then modems. In particular, although the use of the AT protocol is known in computers for controlling modems, that is a wired accessory which connects the computer to a network, the present invention contemplates the use of the AT protocol in a radio communications device for controlling a non-wired accessory that is an accessory which relates to the radio communications. For example, the non-wired accessory may use or control or be controlled by or retransmit signals transmitted over the radio communications link of the radio communications device.